Comparative Pharmacology
Head-to-head clinical analysis: EXTINA versus LAMISIL AT.
Head-to-head clinical analysis: EXTINA versus LAMISIL AT.
EXTINA vs LAMISIL AT
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Antifungal agent that inhibits the enzyme 14α-demethylase, blocking the conversion of lanosterol to ergosterol, an essential component of fungal cell membranes.
Terbinafine inhibits squalene epoxidase, an enzyme in the fungal ergosterol biosynthesis pathway. This leads to accumulation of squalene and depletion of ergosterol, disrupting fungal cell membrane integrity and causing cell death.
2.5% to 3.5% solution applied topically twice daily for 4 weeks.
Terbinafine 250 mg orally once daily for 6 weeks for fingernail onychomycosis or 12 weeks for toenail onychomycosis. Topical: 1% cream applied once daily for 1 week for tinea pedis; 1% solution applied once daily for 1 week for tinea corporis/cruris.
None Documented
None Documented
Terminal elimination half-life is approximately 24-32 hours in adults, allowing once-daily dosing. Half-life may be prolonged in patients with renal impairment.
The terminal elimination half-life is approximately 11-17 hours in healthy adults; however, it increases to about 200-400 hours in the distribution phase from tissues (e.g., skin, adipose). Steady-state is reached after 10-14 days of oral dosing.
Primarily renal excretion of unchanged drug (approximately 80-90% of the absorbed dose), with minor hepatic metabolism and fecal elimination (<10%).
Terbinafine is extensively metabolized in the liver; approximately 80% of a dose is excreted in urine as metabolites, and 20% in feces. Less than 1% is excreted unchanged in urine.
Category C
Category C
Antifungal
Antifungal